fall presentation

Team 4 Baja Chassis

Blair Douglas

Brandon Hawes

Robert Paterson

Ryan Robertson

Supervisor: Dr. Ugursal

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 2

Baja SAE Midwest

3

Hosted by

Rochester Institute

of Technology

June 6-9, 2013

100 Teams from

around the world

What is Baja SAE

2004 Dalhousie Baja1

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 4

Design Requirements

1. Safety: Meet all safety standards

2. Reliability: Perform an off-road test before leaving

for competition.

3. Maximum Width and Length: 64 in (W) x108 in (L)

4. Must fit a person of height 75 in and 250 lb.

5. Maximum Chassis Weight: 400 lb.

6. Minimum Suspension Travel: 6 in.

7. Maximum Turning Radius: 11.5 ft.

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Requirements

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 6

Frame

Compact

Simple

Strong

Meet all Baja SAE Regulations regarding

frame and roll cage design

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Considered Designs

Suspension

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MacPherson Strut

Double A-Arm

3-Link

Twin I-Beam

A-Arm with Trailing

Arm

MacPherson with

Trailing Arm

Considered Designs

MacPherson Strut2

Steering

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4-Bar Linkage / Pitman Arm style

Needs space

Worst case reliability

Rack & Pinion

Considered Designs

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Technical Terms

Positive3 Camber Negative4

Castor5

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 11

Main Features

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Frame

AISI 1020 Pipe

Roll cage

Front section

Rear section

Meets SAE

regulations

Determining Roll Cage

Dimensions

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Frame

Stress Analysis

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Frame

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 15

Double A-arms

Unequal length arms

Ground clearance of

11” at ride height

10” of wheel travel

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Front Suspension

A-Arm Geometry

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Front Suspension

15”

4”

8”

Range of Motion

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Front Suspension

Static Ride Height

Camber Angle = 0º

Full Bump

Camber Angle = -13º

Full Droop

Camber Angle = +5º

Stress Analysis

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Front Suspension

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 20

3-Link

Trailing Arm

Rear Links

Maximized Space

Maximized Travel

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Rear Suspension

Driver

Area

Drivetrain

Space

Maximum Travel

Limited by:

CV Joints

Shock Geometry

Rod Ends

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Rear Suspension

Total Wheel Travel 12”

Installation Ratio 0.45

Coilover

Dual Rate

Rear

Initial rate: 200 lbf/in

Final rate: 600 lbf/in

Front

Initial: 100 lbf/in

Final: 300 lbf/in

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Rear Suspension

Shock Absorber

Slider

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 24

Rack and Pinion

Compact

Reliable

We have two 25

Steering

Castor & Layback

Less work to go straight

Reduced stress over

bumps

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Steering

Toe Correction

Location Matters

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Steering

Turning Radius – 11.5 ft

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Steering

-90

-60

-30

0

30

60

90

-2.5 -1.5 -0.5 0.5 1.5 2.5

Ste

er

An

gle

Steering Rack Translation (in)

Steering Angle Geometry

3.0 x 0 3.0 x 0.5 3.5 x 0

3.5 x 1.0 4.0 x 0 Required Outside Angle

Required Inside Angle

𝛿𝑖 = 𝐿

𝑅 −𝐵2

= 40°, 𝛿𝑜 = 27° Ackermann

Analysis

L=76.5 in

R = 138 in

B = 50 in

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 29

Preliminary

Budget

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Budget Parts List Description Cost

Frame

1020 Steel Tube, 1" OD 0.120" wall Frame Tubing 310$

1018 0.25" x 8" Steel Plate Frame Plating 100$

48" x 48" x 0.032" 6061 Aluminum Firewall & Plating 380$

Subtotal 790$

Suspension

1020 Steel Tube, 1" OD 0.120" wall A-arm & Link Material 70$

4" x 5" 6061 Aluminum Block Upright Material 390$

A-arm Bushing Kit Bushings 50$

1/2"-20, 1/2" ID Steel Rod End Ball Joint 3-Link Joints 60$

3/4"-16, 3/4" ID Steel Rod End Ball Joint Trailing Arm Joints 30$

FOX Float R 18.2" x 5.3" Rear Shocks 600$

FOX Float R 15.6" x 4.3" Front Shocks 600$

2" OD Bearing Bearing 40$

Std. ATV Ball Joint Ball Joints 100$

1" OD 1018 Steel Rod Threaded Insert 30$

Subtotal 1,970$

Steering

3/8"-24, 3/8" ID Steel Rod End Ball Joint Tie Rod End 10$

1" OD, 0.25" wall 6061 Aluminum Tube Steering Column 40$

1" OD 1018 Steel Tube Tie Rods 20$

Subtotal 70$

Hardware

2-1/2" Fully Threaded Grade 5 Bolt Bolts 20$

1/4"-20 Nylon-Insert Grade 8 Nut Nuts 10$

7/16" ID 18-8 Stainless Washers Washers 20$

No.8- 1/2" Zinc Plated Self Tapping Screw Screws 10$

Subtotal 60$

General Baja Parts

K282 Viper Tire Tires 240$

T-9 Pro Baja Wheels Wheels 280$

Subtotal 520$

Overall Subtotal 3,410$

Contingency 580$

Taxes 510$

Total 4,500$

Polaris Parts

Halifax Motorsports Parts

CME Ltd. Materials

Mariner Forge Materials

Shamrock Ranching $ 500

Shell $ 500

Hawkes Blueberries $ 500

Scotia Insulations $ 250

Dalhousie $1800

Total $3550

Income

$ 4,500

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 31

The Next Step

Build frame over break

Order components

Finalize engineering drawings

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Project Status

What is Baja SAE

Requirements

Considered Designs

Frame

Front Suspension

Rear Suspension

Steering

Budget

Project Status

Sponsors 33

Gold Sponsors

34

Sponsors

Gold Sponsors

35

Sponsors

Gold Sponsors

36

Sponsors

Silver Sponsors

CVTech

37

Sponsors

Bronze Sponsors

Committed Sponsors

Polaris

Halifax Motorsports

Canadian Maritime Engineering

Mariner Forge

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Sponsors

Questions

1 2004 DAL Baja, Team 14. http://poisson.me.dal.ca/~dp_04_14/ 2 MacPherson Strut, Auto Repair. http://autorepair.about.com/ 3 1927 Bugatti Type 37 Sport, Axis of Oversteer. axisofoversteer.com

4 Hammer Sport Wheelchair, Colours Wheelchair. colourswheelchairs.com 5 King Bike, kingbike.com

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